Bacteria isolated from perforation peritonitis and their antimicrobial susceptibilities

Bacteria isolated from 25 cases of perforation peritonitis and its antimicrobial susceptibilities were studied. One hundred and forty-six strains including 36 strains of aerobic bacteria, 107 strains of anaerobic bacteria and 3 strains of yeast were isolated from intra-peritoneal fluid obtained at operation. Among aerobic bacteria, Enterobacteriaceae was isolated from 13 cases (52%) out of all, and followed by those of Enterococcus spp. (24%), Pseudomonas aeruginosa (20%), in this order. Among non-spore forming anaerobic Gram-negative bacteria, the isolation rate of Bacteroides fragilis group (64%) was highest, followed by Fusobacterium spp. (40%), Prevotella spp./Porphyromonas spp. (32%) and Bilophila wadsworthia (28%), in this order. The isolation rate of non-spore forming anaerobic Gram-positive bacteria was 60%, and that of Clostridium spp. was 24%. Even by the recent advanced methods, there were 17 strains of anaerobic bacteria, which were not identified by phenotypic-identification levels. Carbapenems and beta-lactams plus beta-lactamase inhibitors have strong antimicrobial activities against both aerobic and anaerobic bacteria. Although metronidazole and minocycline have strong activities against anaerobic bacteria, there were many strains highly resistant to clindamycin.     

我院临床分离厌氧菌的分布特征及药敏谱型

目的 分析厌氧菌标本来源、科室、年龄分布特征及药敏试验结果，为临床经验性治疗和合理使用抗菌药物提供依据。方法 收集2015年1月-2017年11月承德医学院附属医院住院患者所有合格标本中的厌氧菌，经VITEK2 compact ANC进行菌株鉴定，所有菌株使用头孢硝噻吩法检测β-内酰胺酶，使用浓度梯度药敏实验方法检测菌株对13种抗菌药物的敏感性。结果 分离出厌氧菌260株，其中，厌氧消化链球菌94株(36.15%)、脆弱拟杆菌81株(31.15%)、艰难梭菌42株(16.15%)、普雷沃菌属16株(6.15%)、产气荚膜梭菌11株(4.23%)；除艰难梭菌标本来源为粪便外，其他厌氧菌主要分离自脓液；分离厌氧菌最多的科室为产科、老年病科及血液科。药敏结果显示，79株厌氧菌的β-内酰胺酶试验阳性，阳性率为30.4%；脆弱拟杆菌β-内酰胺酶87.6%为阳性，产酶率最高。厌氧消化链球菌对阿莫西林/克拉维酸、替卡西林/克拉维酸、哌拉西林/三唑巴坦100%敏感；脆弱拟杆菌对阿莫西林/克拉维酸、哌拉西林/三唑巴坦敏感率100%；艰难梭菌对氨苄西林/舒巴坦、哌拉西林/三唑巴坦敏感率100%；普雷沃菌属对阿莫西林/克拉维酸、氨苄西林/舒巴坦、替卡西林/克拉维酸敏感率100%；产气荚膜梭菌对青霉素、氨苄西林敏感率100%。甲硝唑对所有菌株均保持很高的敏感性。结论 厌氧菌引起的临床感染常见，不同厌氧菌的分布及药敏结果不尽相同，临床医生可根据菌株的分布特征及药敏结果对厌氧菌感染进行更有效的治疗。     

Bacteria isolated from surgical infections and its susceptibilities to antimicrobial agents--special references to bacteria isolated between April 2003 and March 2004

Tendency of isolated bacteria from infections in general surgery during the period from April 2003 to March 2004 were investigated in a multicenter study in Japan, and the following results were obtained. In this series, 455 strains including 14 strains of Candida spp. were isolated from 191(75.2%) of 254 patients with surgical infections. Two hundred and thirty-nine strains were isolated from primary infections, and 216 strains were isolated from postoperative infections. From primary infections, anaerobic Gram-positive bacteria and aerobic Gram-negative bacteria were predominant, while aerobic Gram-positive bacteria were predominant from postoperative infections. The isolation rate of aerobic Gram-positive bacteria, such as Enterococcus spp. and Staphylococcus aureus were higher from both types of infections. Among anaerobic Gram-positive bacteria, the isolation rate of Peptostreptococcus spp. was the highest from both types of infections. Among aerobic Gram-negative bacteria, Escherichia coli was the most predominantly isolated from primary infections, followed by Klebsiella pneumoniae, Enterobacter cloacae and Pseudomonas aeruginosa in this order, and from postoperative infections, E. coli was the most predominantly isolated, followed by P. aeruginosa, E. cloacae, and K. pneumoniae. Among anaerobic Gram-negative bacteria, the isolation rate of Bacteroides fragilis group was the highest from both types of infections. The isolation rate of anaerobic Gram-positive bacteria from primary infections and that of aerobic Gram-positive bacteria from postoperative infections were high in the last several years. In this series, we noticed no vancomycin-resistant Gram-positive cocci, but a few strains of moderately arbekacin-resistant MRSA. Carbapenm-resistant P. aeruginosa was seen in less than 10 per cents. Last year we noticed that there were cefazolin-resistant E. coli producing extended spectrum beta-lactamase, but there was no highly cefazolin-resistant E. coli in this year. In the next series, increase of both anaerobic bacteria and Enterococcus spp. should be carefully followed up.     

Metronidazole: In Vitro Activity,Pharmacology and Efficacy in Anaerobic Bacterial Infections

Metronidazole is a 5-nitroimidazole that has selective activity against anaerobic microorganisms, including bacteria and protozoa. Intravenous metronidazole has recently been approved by the U.S. Food and Drug Administration for the treatment of serious anaerobic bacterial infections. It is usually bactericidal at low concentrations, and its spectrum of activity encompasses almost all anaerobic bacteria and some capnophilic organisms. Anaerobic bacteria known to be resistant to metronidazole include occasional anaerobic cocci, some nonsporulating gram-positive bacilli and propionibacterium. Metronidazole is the most active antimicrobial agent against Bacteroides fragilis, the most resistant of anaerobic bacteria. Kill-curve studies demonstrate that there is a 2 to 5 log decrease in the number of colony forming units of S. fragilis and Clostridium perfringens within one hour. The only well documented metronidazole-resistant strain is a B. fragilis isolated from the normal flora of a patient on long-term metronidazole therapy for Crohn's Disease. Metronidazole resistance in Trichomonas vaginalis has recently been described in a few strains that are able to survive at increased oxygen tensions. Metronidazole has been shown to be efficacious in certain protozoal infections including trichomonal vaginitis, extraintestinal amebiasis, and giardiasis. Clinical studies have shown metronidazole to be efficacious in the therapy of a variety of anaerobic infections, including non-traumatic brain abscesses, intraabdominal sepsis, pelvic suppuration and necrotizing soft tissue infections. There have been disappointing results in the therapy of anaerobic pleuropulmonary infections with a number of superinfections caused by aerobic bacteria. Since metronidazole lacks any activity against aerobic bacteria, it must be combined with other agents, usually aminoglycosides, in the treatment of mixed infections involving anaerobic and aerobic bacteria.     

A clinical study of asymptomatic bacteriospermia

Asymptomatic bacteriospermia was studied as an entity and its treatment was investigated in 65 subjects who clinically needed their semen tested. The obtained results are summarized as follows. 1. The rate of detection of bacteria in semen was 89.2%, and the rates of detection of aerobic and anaerobic bacteria were 55.4% and 70.8%, respectively. Forty Gram-positive strains were identified among the aerobic bacteria; rates of detection for Staphylococcus epidermidis and Enterococcus faecalis were high, and 6 strains (9.2%) of Streptococcus agalactiae were also present. The rate of detection of Gram-negative bacteria was low; only 3 strains were identified. Among the anaerobic bacteria 90 Gram-positive strains were identified; the rate of detection of Peptostreptococcus (58 strains) was high, and only 11 strains of Gram-negative bacteria were present. 2. Among cefaclor (CCL), cephalexin, lomefloxacin, latamoxef and flomoxef (FMOX), FMOX was, in general, superior to the other drugs in terms of antibacterial activities against those strains isolated from semen. 3. Bacterial changes were observed in the semen specimens from 11 subjects who were subjected to oral administration of CCL (1,500 mg/days). After the treatment, 25 strains of bacteria disappeared but 7 strains remained among 32 strains that were present before treatment, and 23 strains appeared due to superinfection.     

Bacteria isolated from surgical infections and their susceptibilities to antimicrobial agents--special references to bacteria isolated between April 2000 and March 2001

Tendency of isolated bacteria from infections in general surgery and their antimicrobial susceptibilities during the period from April 2000 to March 2001 were investigated in a multicenter study in Japan, and the following results were obtained. The number of cases investigated as objectives was 234 for one year. A total of 388 strains (136 strains from primary infections and 252 strains from postoperative infections) were isolated from 165 cases (70.5% of total cases). In primary infections, anaerobic Gram-positive bacteria were predominant, while from postoperative infections, aerobic Gram-positive bacteria were predominant. Among aerobic Gram-positive bacteria, the isolation rate of Enterococcus faecalis was the highest, followed by that of Staphylococcus aureus from postoperative infections. Among anaerobic Gram-positive bacteria, the isolation rate of Peptostreptococcus spp. was the highest from both types of infections. Among aerobic Gram-negative bacteria, Escherichia coli was the most predominantly isolated from primary infections, followed by Klebsiella pneumoniae and Pseudomonas aeruginosa in this order, and from postoperative infections, P. aeruginosa was the most predominantly isolated, followed by Enterobacter spp. and Klebsiella spp. Among anaerobic Gram-negative bacteria, the isolation rate of Bacteroides fragilis group was the highest from both types of infections. There was no vancomycin-resistant S. aureus nor Enterococcus spp. Among anaerobic bacteria, there were many resistant strains against penicillins and cephems with MICs higher than 100 micrograms/ml, and the same trend was observed among other Bacteroides spp. and Prevotella spp.     

Nationwide surveillance of parenteral antibiotics containing meropenem activities against clinically isolated strains in 2002

The antibacterial activity of meropenem (MEPM) and other parenteral antibiotics against clinical isolates of 899 strains of Gram-positive bacteria, 1500 strains of Gram-negative bacteria, and 158 strains of anaerobic bacteria obtained from 28 medical institutions during 2002 was measured. The results were as follows; 1. MEPM was more active than other carbapenem antibiotics against Gram-negative bacteria, especially against enterobacteriaceae and Haemophilus influenzae. MIC90 of MEPM against Pseudomonas aeruginosa was the lowest of the drugs tested. MEPM showed low cross-resistant rate against both imipenem-resistant P. aeruginosa and ciprofloxacin-resistant P. aeruginosa. MEPM was active against most of the species tested in Gram-positive and anaerobic bacteria, except for multi-drug resistant strains including methicillin-resistant Staphylococcus aureus (MRSA), methicillin-resistant Staphylococcus epidermidis (MRSE). 2. The proportion of extended-spectrum beta-lactamase (ESBL) strains was 3.1% (4 strains) in Escherichia coli and 1.9% (2 strains) in Klebsiella pneumoniae. Carbapenems including MEPM were active against these ESBL strains. In conclusion, the results from this surveillance study suggest that MEPM retains its potent and broad antibacterial activity and therefore is a clinically useful carbapenem; at present, 7 years after available for commercial use.     

Phenelfamycins, a novel complex of elfamycin-type antibiotics. I. Discovery, taxonomy and fermentation

Phenelfamycins A, B, C, E, F and unphenelfamycin have been discovered in the fermentation broth of two soil isolates, designated AB 999F-80 and AB 1047T-33. These isolates were identified as strains of Streptomyces violaceoniger. The antibiotics were selected for their activity against anaerobic bacteria.     

In vitro study on efficacy of combination use of aspoxicillin and beta-lactam preparations (ceftazidime, cefmetazole and aztreonam) against bacteria isolated from abdominal infections]

An in vitro study was done to evaluate combination use of aspoxicillin (ASPC) with each of 3 beta-lactam preparations, ceftazidime (CAZ), cefmetazole (CMZ) and aztreonam (AZT). The results obtained are summarized as follows: 1. ASPC has strong activity against Gram-positive bacteria and anaerobic bacteria, while CMZ and CAZ have strong activity against Gram-negative bacteria. 2. Rates of beta-lactamase producing strains among the isolated bacteria (a total of 383 isolates) were 4.4% among Gram-positive bacteria, 71.6% among Gram-negative bacteria and 89.3% among anaerobic bacteria. The overall rate of beta-lactamase secreting strains among all isolates was 46.5%. 3. Efficacies of combination uses were studied using the FIC index. Combination of ASPC and CAZ was effective against 95.0% of the isolates, ASPC and AZT against 85.7%, and ASPC and CMZ against 83.5%. Combination of ASPC and CMZ showed antagonism in 12.8% of the isolates. In conclusion, combination use of ASPC with any one of CMZ, AZT or CAZ proved to be highly effective. In particular, combination of ASPC and CAZ appeared to be the best in view of complementing antibacterial spectra.     

Nationwide surveillance of parenteral antibiotics containing meropenem activities against clinically isolated strains in 2009

The antibacterial activity of meropenem (MEPM) and other parenteral antibiotics against clinical isolates of 2655 strains including 810 strains of Gram-positive bacteria, 1635 strains of Gram-negative bacteria, and 210 strains of anaerobic bacteria obtained from 30 medical institutions during 2009 was examined. The results were as follows; (1) MEPM was more active than the other carbapenem antibiotics tested against Gram-negative bacteria, especially against enterobacteriaceae and Haemophilus influenzae. MEPM was also active against most of the species tested in Gram-positive and anaerobic bacteria, except for multidrug resistant strains including methicillin-resistant Staphylococcus aureus (MRSA). (2) MEPM maintained potent and stable antibacterial activity against Pseudomonas aeruginosa. The proportion of MEPM-resistant strains to ciprofloxacin-resistant strains or imipenem-resistant strains were 53.1% and 58.0% respectively. (3) The proportion of extended-spectrum beta-lactamase (ESBL) strains was 3.1% (26 strains) in enterobacteriaceae. And the proportion of metallo-beta-lactamase strains was 2.0% (6 strains) in P. aeruginosa. (4) Of all species tested, there were no species except for Bacteroides fragilis group, which MIC90 of MEPM was more than 4-fold higher than those in our previous study. Therefore, there is almost no significant decrease in susceptibility of clinical isolates to meropenem. In conclusion, the results from this surveillance study suggest that MEPM retains its potent and broad antibacterial activity and therefore is a clinically useful carbapenem for serious infections treatment at present, 14 years passed after available for commercial use in Japan.     

Antibiotic susceptibility of periurethral anaerobic microflora in healthy girls

The in vitro susceptibility of sixty-four isolates of periurethral anaerobic bacteria to nine commonly used antibiotics was analyzed. Using a quantitative sampling method, the three predominant anaerobic strains were isolated from each periurethral sample of twenty-one healthy prepubertal girls. The majority of strains showed high sensitivity to ampicillin and phenoxymethylpenicillin, whereas trimethoprim and trimethoprim--sulfamethoxazole showed no or only slight inhibition of growth of most strains. Intermediate sensitivity was found to erythromycin, cefuroxime, pivmecillinam, norfloxacin and nitrofurantoin. Our data suggest that several antibiotics used in paediatric praxis might influence the indigenous periurethral anaerobic microflora. Hypothetically, this may be a factor of importance in the pathogenesis of ascending urinary tract infections.     

糖尿病湿性坏疽细菌感染菌谱及耐药菌谱特点研究

目的 明确糖尿病湿性坏疽感染菌谱和耐药菌谱特点,有针对性的选择抗菌药物。方法 取糖尿病湿性坏疽分泌物进行需氧菌、真菌培养、药敏试验以及厌氧菌培养。结果 357例患者中,细菌培养结果阳性率为100%,共培养出469株细菌,其中感染率革兰阳性菌(G+)45.4%、革兰阴性菌(G-)26.0%、厌氧菌23.7%、真菌4.9%。G+菌中葡萄菌属有5种药物的耐药菌株大于50%、肠球菌属有11种药物的耐药菌株大于50%,G-菌中肠杆菌科有3种药物的耐药菌株大于50%,不动杆菌属和假单胞菌属有8种药物的耐药菌株大于50%,真菌中光滑念珠菌有3种药物的耐药菌株大于50%,其余菌属药物的耐药菌株均小于50%。结论 糖尿病湿性坏疽感染菌谱特点是革兰阳性菌>革兰阴性菌、厌氧菌>真菌,耐药菌谱特点是G+菌感染中的肠球菌属、G-菌感染中的不动杆菌属和假单胞菌属、真菌感染中的光滑念珠菌耐药性较高。     

塞克硝唑体内外抗厌氧菌效果的研究

目的 观察塞克硝唑(secnidazole，SNZ)体内外抗厌氧菌的活性。方法 采用琼脂平板稀释法测定塞克硝唑对200株厌氧菌的MIC90，以厌氧消化链球菌、产气英膜杆菌、脆弱类杆菌和牙龈紫质单胞菌小鼠感染模型测定口服或静脉注射塞克硝唑的体内抗菌活性，实验中以替硝唑和(或)甲硝唑作为对照。结果 塞克硝唑和替硝唑对120株革兰阴性厌氧菌的MIC90分别为l一4，1—2mg／mL，对80株革兰阳性厌氧菌的MIC90分别为4—8，4—16mg／mL，但无显著性差弄(t＝0．36—0．67，P＞0．05)。甲硝唑对上述革兰阴性和革兰阳性厌氧菌的MIC90分别为4—8，16—32mg／mL，明显高于塞克硝唑和替硝唑(t＝2．46—2．82，P＜0．01)。小鼠感染厌氧消化链球菌、产气英膜杆菌、脆弱类杆菌和牙龈紫质单胞菌后，口服塞克硝唑或替硝唑的ED50分别为6．287—12．912，6．943—14．726mg／kg，尾静脉注射塞克硝唑或替硝唑的ED50分别为4．448—8．398，4．380—8．872mg／kg。结论 塞克硝唑体内外抗厌氧菌的效果与替硝吐相似，甲硝唑体外抗厌氧菌作用不如塞克硝唑和替硝唑。     

613株病原菌分布及其主要耐药情况分析

目的分析故城县医院检出的病原菌分布及其主要病原菌的耐药情况,为临床合理用药和控制医院感染提供参考。方法采用恒星细菌分析系统对2012年6月至2012年12月分离的613株病原菌进行鉴定,药敏试验采用琼脂纸片扩散法。结果 2012年下半年共收集非重复临床分离菌株613株,其中革兰阴性菌417株占68%,革兰阳性菌128株占20.8%,真菌68株占11.2%,除真菌外其他病原菌的耐药率较之上半年都明显增加。结论应完善抗菌药物的规范使用,加强细菌培养意识,严格控制医院感染病例的诊断和用药标准,预防抗菌药物耐药率的快速产生。革兰阴性杆菌在住院患者感染中占主要地位,临床医师应警惕革兰阴性菌引起的感染。     

Imipenem/cilastatin. A review of its antibacterial activity, pharmacokinetic properties and therapeutic efficacy

Imipenem is the first available semisynthetic thienamycin and is administered intravenously in combination with cilastatin, a renal dipeptidase inhibitor that increases urinary excretion of active drug. In vitro studies have demonstrated that imipenem has an extremely wide spectrum of antibacterial activity against Gram-negative and Gram-positive aerobic and anaerobic bacteria, even against many multiresistant strains of bacteria. It is very potent against species which elaborate beta-lactamases. Imipenem in combination with equal doses of cilastatin has been shown to be generally well tolerated and an effective antimicrobial for the treatment of infections of various body systems. It is likely to be most valuable as empirical treatment of mixed aerobic and anaerobic infections, bacteraemia in non-neutropenic patients and serious hospital-acquired infections.     

Examination of coumarins,flavonoids and polysaccharopeptide for antibacterial activity

• 1.1. Coumarins, flavonoids and polysaccharopeptide were tested for antibacterial activity.
• 2.2. The bacteria used for this study included clinical isolates of Staphylococcus aureus, Shigella flex-neri, Salmonella typhi, Escherichia coli and Pseudomonas aeruginosa.
• 3.3. Most of the coumarins tested failed to inhibit the bacteria at 25 mg/l. Edultin at 128 mg/l inhibited 4 of the 8 P. aeruginosa strains and 1 of the S. aureus strains tested. O-acetylcolumbianetin and imperatorin did not inhibit any isolate, even at 128 mg/l.
• 4.4. When tested at the dose of 128 mg/l, the flavonoids (rutin, naringin and baicalin) inhibited 25% or less of P. aeruginosa and only baicalin was active against S. aureus.
• 5.5. Arbutin and 4-(β-D-glucopyranosyloxyl)-benzaldehyde inhibited 3 of the 8 P. aeruginosa strains when tested at 128 mg/l.
• 6.6. Polysaccharopeptide from the fungus Coriolus versicolor failed to inhibit any P. aeruginosa or S. aureus strain at 128 mg/l.

     

Bacteria isolated from surgical infections and their susceptibilities to antimicrobial agents. Special references to bacteria isolated between April 1997 and March 1998

The annual multicenter studies on isolated bacteria from infections in general surgery and their antimicrobial susceptibility have been conducted in 19 facilities in Japan since July 1982. This paper describes the results obtained during the period from April 1997 to March 1998. The number of cases investigated as objectives was 215 for one year. A total of 420 strains (170 strains from primary infections and 250 strains from postoperative infections) were isolated from 174 cases (80.9% of total cases). In primary infections, the isolation rate of anaerobic bacteria was higher than in postoperative infections, while in postoperative infections, those of aerobic Gram-positive bacteria and Pseudomonas aeruginosa were higher than in primary infections. Among aerobic Gram-positive bacteria, the isolation rate of Enterococcus faecalis was the highest, followed by Staphylococcus aureus, which was frequently isolated from postoperative infections. Among anaerobic Gram-positive bacteria, Peptostreptococcus spp. and Streptococcus spp. were commonly isolated from both types of infections. Among aerobic Gram-negative bacteria, Escherichia coli was most predominantly isolated from primary infections, followed by P. aeruginosa, Klebsiella pneumoniae in this order, and from postoperative infections, P. aeruginosa was most predominantly isolated, followed by E. coli and K. pneumoniae. Among anaerobic Gram-negative bacteria, Bacteroides fragilis group was the majority of isolates from both types of infections. We found neither vancomycin nor arbekacin resistant strains of S. aureus, and found no vancomycin resistant strains of Enterococcus spp. The susceptibility of P. aeruginosa against carbapenems did not decline in the year 1997, while resistance of B. fragilis group against cephems advanced increasingly.     

Comparison of the antibacterial activity of ticarcillin with other antibacterial agents (author's transl)]

Antibacterial activity of ticarcillin was determined in comparison with that of sulbenicillin, amoxicillin, cefuroxime, clindamycin and metronidazole against anaerobic bacteria which have been isolated from various clinical materials in this hospital. Growth of more than 90% of Gram-negative anaerobic rod bacteria was inhibited by ticarcillin at its concentration of 100 micrograms/ml. Strains resistant to ticarcillin showed cross resistance against both sulbenicillin and amoxicillin. Antibacterial activity of ticarcillin against Gram-positive anaerobic bacteria was found almost equal to sulbenicillin but slightly inferior to amoxicillin. Cefuroxime was found most inferior among the tested six antibiotics when an inoculation level of 10(8)/ml was utilized, but it showed similar activity to ticarcillin when they were tested with 10(6)/ml inoculation. Approximately 10% of bacteroides strains was resistant to clindamycin while all the strains were sensitive to metronidazole.     

Bacteria isolated from surgical infections and its susceptibilities to antimicrobial agents--special references to bacteria isolated between April 2001 and March 2002

Isolated bacteria from infections in general surgery during the period from April 2001 to March 2002 were investigated in a multicenter study in Japan, and the following results were obtained. In this series, four hundred and twenty strains were isolated from 175 (79.2%) of 221 patients with surgical infections. One hundred and eighty-six strains were isolated from primary infections, and 234 strains were isolated from postoperative infections. From primary infections, anaerobic Gram-positive bacteria were predominant, while from postoperative infections, aerobic Gram-positive bacteria were predominant. Among aerobic Gram-positive bacteria, although the isolation rate of Staphylococcus aureus was the highest, followed by that of Enterococcus faecalis from primary infections, the isolation rate of E. faecalis was the highest from postoperative infections. Among anaerobic Gram-positive bacteria, the isolation rate of Peptostreptococcus spp. was the highest from both types of infections. Among aerobic Gram-negative bacteria, Escherichia coli was the most predominantly isolated from primary infections, followed by Klebsiella pneumoniae and Pseudomonas aeruginosa in this order, and from postoperative infections, P. aeruginosa was the most predominantly isolated, followed by Enterobacter spp., E. coli and Klebsiella spp. Among anaerobic Gram-negative bacteria, the isolation rate of Bacteroides fragilis group was the highest from both types of infections. The isolation rate of aerobic Gram-negative bacteria from primary infections and that of aerobic Gram-positive bacteria from postoperative infections were high in the last several years. We noticed no vancomycin-resistant Gram-positive cocci.     

In vitro activity of vancomycin and teicoplanin against anaerobic bacteria

The in vitro activity of vancomycin and teicoplanin, a new glycopeptide antimicrobial, was determined against a total of 286 anaerobic bacteria including Bacteroides fragilis group (100), B. melaninogenicus (21), B. bivius (16), Fusobacterium spp. (15), Peptococcus spp. (20), Peptostreptococcus spp. (21), Clostridium perfringens (23), C. difficile (41) and Propionibacterium acnes (29). Minimum inhibitory concentrations (MIC) were determined using an antimicrobial incorporation technique in Wilkins-Chalgren agar approximately 10(4) colony forming units (cfu) contained in 10 microliters Wilkins-Chalgren broth, which was applied to the surface of the agar plates using a multipoint inoculator. Following inoculation, plates were incubated for 48 h at 37 degrees C in an anaerobic atmosphere. Both vancomycin and teicoplanin were highly active against all the Gram-positive anaerobic bacteria examined, 90% of all isolates being inhibited by 0.5 micrograms/ml of either antimicrobial. Isolates of B. fragilis group and Fusobacterium spp. were resistant to vancomycin (MIC90 64 micrograms/ml) and teicoplanin (MIC90 128 micrograms/ml). Unexpectedly, isolates of B. melaninogenicus and B. bivius which were resistant to vancomycin (MIC90 64 and 128 micrograms/ml respectively) were sensitive to teicoplanin (MIC90 2 and 2 micrograms/ml respectively).